Description

This invention relates to a wireless information processing
terminal that has wireless communication functions like a PHS (Personal
Handyphone System) and a method of controlling the same and, more
particularly, to a wireless information processing terminal that has
additional information processing functions like a PDA (Personal Digital
Assistant) and a method of controlling the same. More specifically, this
invention relates to a wireless information processing terminal of the
type, which is connectable to a BBS (Bulletin Board System) or a provider
of the Internet (or to an access point prepared by such a provider), and
a method of controlling the same.

In the prior art, various types of "Telecomputing Systems" have
been developed and commercially exploited for connecting remotely located
computers together by using a communication network such as a PSTN
(Public Switched Telephone Network). In Japan, for example, with
enforcement of the telecommunications business code law in 1985, the
so-called "Personal Computer Network" has flourished remarkably. A
computer user, who enters into a contract with a service provider of a
personal computer network, is allowed to access a given host (i.e.,
information server) of the service provider.

WO 94/29995 A1 discloses information retrieval in a cellular system, wherein a database associated with a base station
stores telephone number of emergency assistance organizations associated with various geographic areas. A mobile terminal
requesting emergency assistance provides positional information to the base station, and the database is accessed
to transmit to the terminal the telephone number of the emergency organization which is most
appropriate for the location of the mobile terminal.

A major trend of telecomputing in the recent years is to exploit
the Internet. As well known in the art, the Internet is a generic name of
networks around the whole world interconnected together based on the
network "NSFnet", which was established in 1970s on an investment of
National Science Foundation (U.S.A.). While the Internet was originally
intended to construct an international network for connecting
universities and/or research institutions in 54 countries to exchange
information among them, as a respective server (mainly, UNIX workstation)
installed at each of the universities and/or research institutions
repeated interconnections independently, it has grown into an enormous
collection of networks covering the whole world (the present day's
Internet comprises several hundred thousands of servers scattered around
the whole world). Remotely located server machines are interconnected in
accordance with a protocol called "TCP/IP (Transmission Control Protocol/Internet
Protocol), whereby a data transfer or a communication on a
BBS may be made between the connected computer systems.

While the prior (i.e., the originally intended) Internet was tinged
with connections between computer systems in a UNIX environment, with its
opening to the general public in 1994 and the resultant advent of
providers (service providers), it has widespread among general business
organizations and/or individual users in an accelerative manner. For
example, major service providers of personal computer networks in Japan
(e.g., "PC-VAN", "NiftyServe" and the like) are now providing Internet
connection services as well.

Since the Internet comprises a collection of networks, each having
a different administrative/controlling organization with a different
policy, there is no centralized organization to inclusively manage the
Internet as a whole. In other words, each of the servers (e.g., database
servers, file servers) scattered around the whole world is locally
managed by a user in a network respectively. Also, via a server connected
to the Internet, each user of the Internet may act as an information
provider, or may access any information on the Internet in a seamless
manner. This is quite contrast to the conventional "Personal Computer
Network", which allows limited access to a given host only. Incidentally,
for the purpose of distinguishing from "Internetworking" that means to
connect networks of certain business organizations together to construct
a wide area network, the Internet is commonly denoted in English as the
aforementioned proper noun ("the Internet").

As described, substance of the Internet does not reside in a single
computer system that is administered by a particular business
organization or corporation. Rather, its substance resides in a
collection of interconnected networks, each comprising a number of
computer systems (server machines) for storing information respectively.

In order to make use of the Internet, a user must connect his/her
own computer (personal computer) to a subscriber server as its client. If
the user is a researcher or a student, his/her computer may be connected
as a client to a server machine owned by a research institute or a
college to which the user belongs. On the other hand, in case of a
general or regular user, he/she must enter into a contract with a
commercial internet service provider (hereinafter called "internet
connection provider" or "service provider"). As the commercial internet
services, there are "IBM internet connection service" of IBM Japan, Ltd.
or "BEKKOAME/INTERNET" of Bekkoame Internet and the like.

While there are several types of contracts with a service provider,
one of the services that is most easily available to an individual user
is the so-called "dial-up IP (Internet Protocol)". As well known in the
art, any computer system (server) connected to the Internet must acquire
an identification number called "IP address". In addition to its own IP
address for connecting to the Internet, a service provider has a number
of IP addresses, which are sequentially assigned to each of the
contracted users who request an Internet connection via a telephone line
(i.e., dials-up), thereby to provide a window of the Internet. Also, most
of the service providers have established connection points (i.e., access
points) to be dialled-up by contracted users in all major cities of the
country and, thus, a user may save his/her telephone charges by dialling
the nearest access point. In other words, a user may use a telephone line
and a modem for connecting his/her own PC to a server of a service
provider as its client, thereby to establish a connection to the
Internet. Further, through this server, the user may access data at
another server (e.g., Web page) on the Internet.

On the other hand, a great variety of information equipment has
been connected to the Internet. That is, when the Internet was beginning
to spread, personal computers (PCs) installed at fixed sites such as
offices, homes and the like were dial-up IP connected using wires
primarily. However, in these days, it is not unusual to establish a
dial-up IP connection by using a PDA or PHS that has further improved
portability/mobility over a notebook PC. Under a mobile environment, it
is very rare to do a hard job using a word processing program (document
editing) or a spreadsheet program. Rather, it is mostly sufficient to do
a lighter job such as transmission of reports in the form of electronic
mails. while a PDA or PHS is merely capable of executing a simple
application alone due to its limited input/output and processing
capabilities, nevertheless it is capable of exchanging electronic mails
and displaying data (e.g., text portions only). This is why a PDA or PHS
having a smaller size and a lighter weight is desired under a mobile
environment, rather than a PC adhering to the full specifications.

More particularly, in case of using a terminal such as a PHS that
implements wireless communication functions, there is no need for a user
to care about position of a modular jack. That is, there is no need for a
user of the Internet to stay at a particular site at all and, thus, the
user may freely establish a dial-up IP connection under a mobile
environment such as outdoor or any location where the user moves. An
advantage of connection to the Internet by means of a wireless
communication terminal resides in that its user is allowed to distribute
an electronic mail or to participate in BBS based on data/information
acquired under a mobile environment, thereby to maintain immediateness or
freshness of data. In other words, a wireless communication terminal of
portable type may become an information source having improved mobility.
Further, a PHS is better than a cellular telephone in terms of lower
manufacturing/operation costs, since a PHS has no limitation of frequency
assignment or the like.

Even under a mobile environment, a user may be freely connected to
the Internet for exchanging desired data or electronic mails. However,
under a mobile environment, the nearest access point is not necessarily
fixed. In the same manner as a user of a PHS or cellular telephone moves
across cells, a mobile user is able to freely move across access points.
As for a desktop PC installed at a particular site in a fixed manner, its
nearest access point is also fixed and, thus, the previously setup access
point may be used without any change. However, this is not true for a
mobile user as set forth above.

There is no doubt that making a dial-up IP connection from the
nearest access point requires the lowest cost. However, it will be
extremely difficult or cumbersome for a user to store by himself/herself
the nearest access point (telephone number) for each moving location
respectively, or to change setup contents of a program.

It is, therefore, an object of this invention to provide an
improved wireless information processing terminal that has additional
information processing functions like a PDA, and a method of controlling
the same.

It is another object of this invention to provide an improved
wireless information processing terminal that is connectable to a BBS or
to an access point prepared by an internet provider for communicating
data, and a method of controlling the same.

It is yet another object of this invention to provide an improved
wireless information processing terminal that is connectable to an
appropriate one of the access points prepared by an internet provider
even under a mobile environment (i.e., at each moving location), and a
method of controlling the same.

This invention has been made in consideration of said problems and
its first aspect resides in a wireless information processing terminal as
claimed in claim 1.

A second aspect of this invention resides a method of controlling a
wireless information processing terminal as claimed in claim 5.

A third aspect of this invention resides in a computer readable
storage medium for storing in a tangible form a computer program
executable on a wireless information processing terminal as claimed in
claim 9.

A wireless information processing terminal according to a preferred
embodiment of the invention (alternatively called "wireless mobile
station" or "mobile station"), which is represented by a PHS, establishes
a communication with another terminal (e.g., PHS or a conventional
telephone connected by a wire) via at least one wireless base station
(alternatively called "base station"). In general, two or more base
stations are connected together by a communication network such as a PSTN
or an ISDN (Integrated Services Digital Network). Accordingly, a mobile
station dials-up to the nearest access point via a base station, thereby
to establish a dial-up IP connection.

A mobile station may transmit/receive data to/from one base station
within a certain range, which is limited to a given area centering around
the base station due to attenuation of radiowaves or the like caused by
environmental factors. In general, such an area is called "wireless cell"
(or simply "cell"). When a mobile station enters a wireless cell that is
served by one base station and this mobile station registers its current
location at said one base station, this mobile station may establish a
wireless communication with said one base station. Also, each base
station may accommodate a plurality of mobile stations within its own
wireless cell, thereby to control access to each of the mobile stations.

In case of using a PHS that is defined to output a weaker radiowave
than a cellular telephone, a wireless cell has to have a limited coverage
with the radius of hundreds of meters at most. Stated in another way, in
such a case, it may frequently happen that a PHS moves across wireless
cells. For this reason and to make preparations for repetitive location
registration operations, a PHS base station periodically (at intervals of
1.2 seconds in accordance with the standards for the PHS public service)
transmits a base station-ID (CS-ID) for indicating its existence, whereas
a PHS mobile station responds to receipt of the base station-ID for
registering its location at the base station. This invention has been
made in consideration of the facets that a PHS base station transmits a
base station-ID, and that a base station-ID contains location information
(because a base station does not move at all).

A wireless information processing terminal (PHS) of this invention
periodically receives notification information from a wireless base
station, which serves a wireless cell covering the current location of
this terminal. As well known in the art, a predetermined field of this
notification information is allocated to contain a base station-ID
(CS-ID), whereas predetermined bit positions in this CS-ID are rendered
to contain an NTT exchange identification number that is available as the
location information (to be described below). Note here that "NTT" stands
for Nippon Telegraph & Telephone Corp.

This terminal previously stores in its own memory an association
table, which associates NTT exchanges' identification numbers with
telephone numbers of the access points nearest to these exchanges
respectively. Since physical locations of the NTT exchanges are generally
fixed, an association between each exchange and the access point nearest
to each exchange may be uniquely determined in most cases (however, there
may be an exceptional case where a plurality of exchanges are associated
with an identical access point).

When a user of this terminal requests connection to the Internet,
this terminal extracts a CS-ID (more precisely, an NTT exchange
identification number) from notification information transmitted from a
current wireless base station and, then, retrieves the association table
provided in its own memory, thereby to acquire a telephone number of the
access point nearest to the current location.

Thus, this terminal dials-up to the acquired access point to
establish an internet connection. As a result, this terminal is allowed
to download an electronic mail destined therefor, a Web page (HTML file
or the like) stored in a disk of a given Web server and the like.
Alternatively, this terminal is allowed to transmit data contained
therein (or a file and/or an electronic mail edited on this terminal) to
another computer system connected to the Internet, or to upload such data
to a disk of a given Web server.

To summarize, in case of connecting an ever-moving wireless
information processing terminal to the Internet, the nearest access point
is automatically selected such that a dial-up IP connection is
established. Thus, there is no need for a user to know the current
location or the access point nearest to the current location.

Further, the computer readable storage medium relating to the third
aspect of this invention define a structural or functional collaborative
relationship between a computer program and the storage medium for
implementing functions of a wireless information processing terminal of
this invention. In other words, by mounting the storage medium onto this
terminal (or installing the computer program into this terminal), it
becomes possible to demonstrate the collaborative functions on this
terminal, thereby to obtain advantages similar to those of the first
aspect of this invention.

Incidentally, while an association between a CS-ID (i.e., location
information of each wireless base station) and an access point may be
previously stored into the memory internal to the terminal, such an
association may be alternatively learned one after another for storing
therein. If a user's sphere of action is limited (this may be applied to
a user who constantly commutes to and from his/her office without
dropping in another place), there will be no need to support information
of access points in broader areas. To support only a required number of
access points in this way, it becomes possible to save memory capacity.

If a user of a wireless information processing terminal requests
connection to the Internet, and if an access point associated with the
current wireless base station is not yet registered at that time, the
user may be prompted to enter a telephone number of a desired (in most
cases, the nearest) access point. In response thereto, this terminal
dials-up to the entered telephone number, and registers the entered
telephone number in association with a CS-ID (more precisely, an NTT
exchange identification number) of the current wireless base station. In
so doing, when connection to the Internet is subsequently attempted from
the cell served by the same wireless base station, the previously
registered access point is automatically selected, thereby to
automatically establish a dial-up IP connection.

An embodiment of the invention will now be described with reference
to the accompanying drawings, in which:

Fig. 1 is a diagram illustrating an external view of a wireless
information processing terminal 100 adapted for implementing this
invention.

Fig. 2 is a diagram schematically illustrating an internal hardware
configuration of the wireless information processing terminal 100 adapted
for implementing this invention.

Fig. 3 is a flow chart illustrating a first operational example of
the wireless information processing terminal 100.

Fig. 4 is a diagram schematically illustrating a format of a
notification information slot transmitted by a PHS base station.

Fig. 5 is a flow chart illustrating a second operational example of
the wireless information processing terminal 100.

Referring now to the drawings, Fig. 1 shows an external view of an
information processing terminal 100 adapted for implementing this
invention. It should be understood that this terminal 100 is provided
with both functions of the so-called PDA (Personal Digital Assistant) and
PHS (Personal Handyphone System) for a wireless communication.

As shown in Fig. 1, the information processing terminal 100
comprises a relatively thin first housing 10 and a relatively thick
second housing 20. The second housing 20 is pivotally supported by a
hinge 30 at one end of the first housing 10.

The first housing 10 has an interface defined by PCMCIA (Personal
Computer Memory Card International Association) and JEIDA (Japan
Electronic Industry Development Association). An exemplary external
computer system connectable to the information processing terminal 100 of
the present embodiment is a personal computer with a PC card slot, which
conforms to the specification of OADG (PC Open Architecture Developer's
Group), such as a notebook PC called "IBM ThinkPad 765" ("ThinkPad" is a
trademark of IBM Corp.), commercially available from IBM Japan, Ltd.

On the top surface of the first housing 10, a keyboard 12 including
a plurality of keypads is provided. The keyboard 12 comprises ten keys,
function keys, cursor keys, a power switch, as well as a key input
control circuit embedded in the housing for generating a scan code in
response to a key input. The keyboard 12 used as input means for the PDA
functions, and in case of using the terminal 100 as a PHS, it is used for
entering a telephone number or switching operation modes. Further, on the
top surface, an upper portion of a microphone 13 for inputting audio
signals is exposed. The microphone 13 is used for a speech conversation
when the terminal 100 is used as a PHS.

On the surface of the second housing 20, a liquid crystal display
21 is provided as output means for the PDA functions. In the present
embodiment, the display 21 has a relatively large screen of 200 x 320 dot
resolution. On the display 21, processed data (e.g., PIM (Personal
Information Manager) data downloaded from a PC, contents of a Web page
and/or an electronic mail received at the PHS section, or the like) is
displayed.

A top edge portion of the second housing 20 is formed in a
semicylindrical shape. On the surface of this semicylindrical shape, a
speaker 22 for outputting a voice is provided. Further, at the left side
edge of the second housing 20, an antenna 23 for wireless
transmission/reception is mounted along a longitudinal axis of the second
housing 20.

In the first housing 10, there is mounted a PCMCIA interface 51. In
the present embodiment, the PCMCIA interface 51 is a circuit that
includes functions for implementing an interface protocol with a
connected external computer system, as well as other functions for
generating a scan code in response to a key input on the keyboard 12.
Such a circuit may be made by using the ASIC (Application Specific
Integrated Circuit) technology. Data downloaded from an external computer
system (not shown) is captured into the terminal 100 via this PCMCIA
interface 51.

In the second housing 20, there is mounted almost all components
for the PDA functions to process computer data, together with major
components for the PHS functions to implement a wireless communication.
It should be understood in this respect that the hatched hardware blocks
shown in Fig. 2 are those components dedicated to the wireless
communication functions.
A MISC controller 61 is provided with functions for feeding signals from
the PCMCIA interface 51 to an internal bus 62.

On the internal bus 62, each component is interconnected. Of these
components, a CPU 63 is a main controller for controlling the PDA
functions of the information processing terminal 100. CPU 63 is also
arranged to control the display 21.

ROM 55 is a read-only memory, which permanently stores code groups
for controlling hardware operations in the terminal 100. RAM 65 is a
writable volatile memory, which is primarily used as a working area of
CPU 63. A flash memory 66 is an erasable non-volatile memory, which is
used for retaining, for example, confidential data of the terminal 100.
In case of using the terminal 100 as a PDA, its operating system (OS) and
applications (e.g., "Dialer" (tentatively named) for calling a called
party's telephone, "Browser" (tentatively named) for browsing a Web page
on the Internet, "Mail" (tentatively named) for exchanging an electronic
mail via the Internet, and the like) may be saved in the flash memory 66.

A voice CODEC 67 is a dedicated circuit for expanding/compressing
voice data. For example, voice data inputted via the microphone 13 is
compressed by the voice CODEC 67 and is subsequently captured into the
terminal 100. Conversely, voice data expanded by the voice CODEC 67 is
outputted by the speaker 22 as a voice.

A modem 66 is a dedicated circuit for modulating computer data as
an analog signal available on a telephone line, or conversely, for
demodulating a received analog signal as computer data. For example,
computer data received from an external computer system via the PCMCIA
interface 51 and the MISC controller 61 is modulated by the modem 66,
compressed by the voice CODEC 67, and then converted into a wireless code
for transmission from the antenna 23. Conversely, a received wireless
code is demodulated by the modem 66 and, then, it is processed by the
internal CPU 63 or a connected external computer system (not shown).

A wireless communication means 71 is a main controller for
administering the PHS functions of the terminal 100. Also, this wireless
communication means 71 supports a variety of functions as a PHS
telephone, including but not limited to calling on telephone directory,
redial, history of call incoming, dial lock, calling party number
identification, automatic answering telephone service, and the like. A
protocol ROM 73 permanently stores control code for performing operations
in accordance with predetermined communication schemes. In general,
communication schemes are different for each of the carriers (e.g.,
Astel, DDI Pocket and the like).

RF means 72 is a dedicated circuit for implementing input/output of
wireless data via the antenna 23. The RF means 72 outputs transmission
data passed from the wireless communication means 71 as wireless data, or
conversely, it captures wireless data received via the antenna 23 into
the terminal 100.

The terminal 100 is provided with a battery 81 as a primary power
source. For the battery 81, a secondary battery such as a lithium-ion
battery may be adopted. Output terminal voltage of the battery 81 is
level converted by a DC-DC converter 82 and then fed to each component.
Also, there is provided a backup battery 83.

Note that additional electronic circuits or the like other than
those shown in Fig. 2 are required to construct the information
processing terminal 100 for implementing both of the PDA functions and
the PHS functions. However, these components are not described in the
present specification, since they are well known in the art and yet they
do not pertain to this invention. Also, it should be understood that for
brevity of the drawings, only a portion of the connections among the
illustrated hardware blocks is shown.

In the following, we will describe detailed operations of the
information processing terminal 100 of the present embodiment configured
as set forth above, as well as functions of this invention.

Fig. 3 shows a flow chart of a first operational example of the
information processing terminal 100. In this example, it is assumed that
the terminal 100 is previously rendered to implement therein (e.g., in a
memory such as ROM 64, flash memory 66 or the like) an association table
for associating each PHS support area (i.e., each base station) with its
nearest access point of a destined internet (or BBS) provider (step
S100).

Table 1, as set forth below, schematically illustrates the
association table. In this table, one record is prepared for each of the
NTT exchanges respectively, and this record includes fields for
containing an NTT exchange identification number and a telephone number
of its associated access point. Since locations of the NTT exchanges are
physically fixed, and they imply locations of calling parties (callers),
it is possible to determine the nearest access point by using an NTT
exchange identification number. Incidentally, in regard to such an area
with an NTT toll number where no access point of the internet/BBS
provider exists, data of the nearest access point may be conveniently
retained, or an NTT toll number may be simply calculated to select an
access point.

This association table may be permanently stored into ROM 64 of the
information processing terminal 100 by its manufacturer before its
shipment, or this table may be alternatively written into the flash
memory 66 such that content thereof is appropriately updated. In
consideration of a trend that new access points are further constructed
in the near future, the latter approach will be more useful (an update
method of this table may rely on downloading from an external computer
system via the PCMCIA interface 51, or a wireless transmission from the
contracted internet/BBS provider).

In response to movement across cells, the information processing
terminal 100 performs location registration at the base station of the
newly entered cell, as well known in the art (step S104). In accordance
with the well known standards for the PHS public service, each base
station is defined to periodically (1 slot per 1.2 second interval)
transmit notification information for location registration of a PHS
mobile station.

Fig. 4 schematically shows a format of this notification
information. R and GT fields contain ramp bits and guard bits
respectively, each providing a sufficient margin for transient response.
SS and PR fields contain a start symbol and preamble respectively, each
forming continuous signals of 2T used for bit synchronization. UW field
contains a unique word used for frame synchronization. CI field contains
a channel identifier, which is equal to 4 (hex) for the notification
information. I field contains 62 bits allocated to an information
message, and it describes a configuration of a super-frame or the like in
a predetermined format. CRC field contains a CRC (cyclic redundancy
check) code.

ID field contains a base station-ID (CS-ID), which normally
comprises 42 bits. This CS-ID field is further divided into subfields,
including "public/private", "carrier identification number",
"intra-carrier identification number", "NTT exchange identification
number" and "additional information" (However, structure of the CS-ID may
be slightly changed for each of the carriers). In the "NTT exchange
identification number" subfield, there is described an identification
number of an NTT exchange that covers the current base station. Note that
such an identification number has a one-to-one correspondence with an NTT
toll number (e.g., "03" for Tokyo, "045" for Yokohama).

Referring to Fig. 3 again, if the terminal 100 acquires a CS-ID,
the process returns to step S102 again, where it waits for either
entrance of the terminal 100 into the next cell or starting of given
terminal software. Incidentally, the acquired CS-ID of the current base
station has been saved in a given address of the flash memory 66, for
example.

It is assumed here that a user of the information processing
terminal 100 starts terminal software such as "Browser" for browsing a
Web page, "Mail" for exchanging an electronic mail or the like (step
S106). Since starting of "Browser" or "Mail" is subject to connection to
the Internet, it requests another terminal software, "Dialer", to connect
to the Internet.

First, "Dialer" extracts an NTT exchange identification number from
the current CS-ID previously acquired and, then, retrieves a record for
this identification number from the association table as set forth in
TABLE 1, thereby to acquire a telephone number of an access point that is
nearest to the current location (step S108). Next, "Dialer" dials the
acquired telephone number of this access point (step S110).
When the terminal 100 is authenticated by the selected access point and a
communication therewith is established, a dial-up connection to the
contracted provider is accomplished. As a result, the terminal 100 is
allowed to access a desired Web server for acquiring a Web page, or to
exchange an electronic mail (step S112).

When a user closes the active terminal software (e.g., "Browser" or
"Mail") after having done an intended work such as browsing of a Web page
or exchanging of an electronic mail, the currently established
communication with the access point is disconnected (step S114).
Thereafter, the process returns to step S102, where it waits for either
entrance of the terminal 100 into the next cell or starting of given
terminal software.

In Fig. 5, there is shown a flow chart of a second operational
example of the wireless information processing terminal 100. In the flash
memory 66, there is provided an association table for associating each
PHS support area with its nearest access point of a destined internet (or
BBS) provider. While the format of this association table is
substantially the same as that of TABLE 1, it is assumed here that at the
time of shipping the terminal 100, this table is initially in a blank
condition, and whenever the terminal 100 is subsequently connected to the
Internet or BBS under a mobile environment, one or more records are added
or updated (i.e., learned) respectively (step S200). In this sense, this
association table in the present example has a role of a "communication
record table" of the terminal 100.

Next, it is assumed at this stage that a user carrying the
information processing terminal 100 moves into another cell (step S202).

In response to movement across cells, the information processing
terminal 100 performs location registration at the base station of the
newly entered cell, as well known in the art (step S204). In accordance
with the well known standards for the PHS public service, each base
station is defined to periodically (1 slot per 1.2 second interval)
transmit notification information for location registration of a PHS
mobile station. Such notification information, format of CS-ID included
therein, or the like were already described above, with reference to Fig.
4.

If the terminal 100 acquires a CS-ID along with location
registration, the process returns to step S202 again, where it waits for
either entrance of the terminal 100 into the next cell or starting of
given terminal software. Incidentally, the acquired CS-ID of the current
base station has been saved in a given address of the flash memory 66,
for example.

It is assumed here that a user of the information processing
terminal 100 starts terminal software such as "Browser" for browsing a
Web page, "Mail" for exchanging an electronic mail or the like (step
S206). Since starting of "Browser" or "Mail" is subject to connection to
the Internet, it requests another terminal software, "Dialer", to connect
to the Internet.

. First, "Dialer" extracts an NTT exchange identification number from
the current CS-ID previously acquired and, then, retrieves a record for
this identification number from the past "communication record table"
(step S208). If there is any communication record for the current NTT
exchange identification number, this record is referenced to acquire a
telephone number of the nearest access table. Then, "Dialer" dials the
acquired telephone number of this access point (step S216).

on the other hand, if there is no communication record for the
current NTT exchange identification number for any reason (e.g., a first
occasion to access the Internet from the current cell), a user is
prompted on the display 21, for example, to manually input a telephone
number of a desired access point (step S212). Thereafter, a record that
describes an association between the inputted telephone number of this
access point and the current NTT exchange identification number is
written into the "communication record table" (step S214). Then, the
telephone number of this access point is dialled accordingly.

When the terminal 100 is authenticated by the selected access point
and a communication therewith is established, a dial-up connection to the
contracted provider is accomplished. As a result, the terminal 100 is
allowed to access a desired Web server for acquiring a Web page, or to
exchange an electronic mail (step S218).

When a user closes the active terminal software (e.g., "Browser" or
"Mail") after having done an intended work such as browsing of a Web page
or exchanging of an electronic mail, the currently established
communication with the access point is disconnected (step S220).
Thereafter, the process returns to step S202, where it waits for either
entrance of the terminal 100 into the next cell or starting of given
terminal software.

Because of constraints such as manufacturing costs, packaging
spaces and the like, it would be difficult for certain types of the
information processing terminals 100 to have association tables of a
sufficient number of access points that are scattered around the whole
PHS support areas (e.g., all parts of Japan). In such a case, the
aforesaid second operational example will be advantageously applied.
Further, in another case where a user's sphere of action is limited to
commuting areas and/or specific business-trip cities, which leads to a
relatively small number of records to be contained in the association
table, the aforesaid second operational example will be advantageously
applied as well to save the required memory capacity.

As described above in detail, in accordance with this invention, it
is possible to provide an improved wireless information processing
terminal that is connectable to an appropriate one of the access points
prepared by an internet provider even under a mobile environment (i.e.,
at each moving location), and a method of controlling the same.

Claims (9)

A wireless information processing terminal (10) which is movable across
a plurality of wireless cells, and executes a wireless data exchange
operation with a wireless base station serving one of said wireless cells
where said terminal currently resides, comprising:

communication means (71, 72) for executing a communication with a wireless base
station; and

means for extracting a base station-ID from data received from a
wireless base station;

said terminal characterized by:
memory means (64, 66) for storing associations between the base station-IDs
and the nearest access points of a provider;

access point retrieving means for accessing said memory means and
retrieving one of the access points associated with a current wireless
base station; and

means for attempting to establish a connection to the retrieved
access point.

A wireless information processing terminal as claimed in claim 1
further comprising:

display means (21) for displaying processed data and the like;

data download means for downloading data through the connected access
point; and

display control means (63) for causing said display means to display the
downloaded data.

A wireless information processing terminal as claimed in claim 1 or
claim 2 further comprising:

input means (12) for allowing a user to input data and a command; and
writing means for writing a user inputted telephone number of an access
point of a provider into said memory means in association with the base
station-ID of a current wireless base station;

wherein said memory means is adapted to store data and a program
and said access point retrieving means is responsive to a user's request
for connecting to an access point, for accessing said memory means and
retrieving the telephone number of an access point associated with the
base station-ID of the current wireless base station.

A wireless information processing terminal as claimed in claim 2
wherein said means for establishing a connection includes means for
dialling to the retrieved access point;
said data download means downloads Web data through the dialled access
point; and
said display control means causes said display means to display the
downloaded Web data.

A method of controlling a wireless information processing terminal
which is movable across a plurality of wireless cells, said terminal
having a table for describing associations between base station-IDs and
the nearest access points of a provider, and executing a wireless data
exchange operation with a wireless base station serving one of said
wireless cells where said terminal currently resides, said method
comprising the steps of:

receiving notification information from a wireless base station
serving one of said wireless cells where said terminal currently resides;
extracting a base station-ID from said received notification information;
retrieving said table to acquire one of the access points associated with
the base station-ID; and

attempting to establish a connection to the acquired access point.

A method as claimed in claim 5 wherein said terminal has input
means for entering data and said retrieving step retrieves from said
table a record relating to the base station-ID, said method comprising
the steps of:

responding to successful finding of said record relating to the
base station-ID in said table for attempting to establish a connection to
the access point described in said record;

responding to unsuccessful finding of said record relating to the base
station-ID in said table for prompting a user to enter information about
an access point; and

registering a record for associating the entered access point with
the base station-ID into said table.

A method as claimed in claim 5 or 6 wherein said terminal has
display means for displaying data, said method comprising the steps of:

subsequent to establishment of the connection, downloading data through
the connected access point; and

causing said display means to display the downloaded data.

A method as claimed in claim 7 wherein said retrieving step
retrieves said table to acquire a telephone number of an access point
associated with the base station-ID, said connection step includes
dialling to the acquired telephone number of said access point, said
downloading step downloads web data through the connected access point,
and said display means displays the downloaded Web data.

A computer readable storage medium for storing in a tangible form a
computer program executable on a wireless information processing terminal
which is movable across a plurality of wireless cells, said terminal
having a table for describing associations between base station-IDs and
the nearest access points of a provider, and executing a wireless data
exchange operation with a wireless base station serving one of said
wireless cells where said terminal currently resides, said computer
program comprising:

a routine for receiving notification information from a wireless
base station serving one of said wireless cells where said terminal
currently resides;

a routine for extracting a base station-ID from said received
notification information;

a routine for retrieving said table to acquire one of the access points
associated with the base station-ID; and

a routine for attempting to establish a connection to the acquired access
point.